This invention relates to a pallet changing mechanism for a machine tool which can move and connect a pallet loaded with an attachment such as an automatic index head on the side of the machine tool and can operate the attachment without hindrance, and a connector device used therefor.
A pallet changer has its object wherein the pallet changer is combined with an automatic machine tool like a machining center to effect an automatic unmanned operation for many hours, thus improving its service efficiency to enhance productivity. At this time, works are loaded on the pallet and are carried in and out on a processing table of the machine tool. In a case where the processing requires, for example, an angle indexing function, it is necessary to load works on the pallet through a high degree of an attachment such as an automatic index head.
Such an attachment has a drive portion and a detection portion so that a drive signal from an external source is inputted into said drive portion, and the result thereof is transmitted to the external as a feed back signal from the detection portion to realize operations such as indexing of a fixed angle. Accordingly, it is necessary to provide an input and output cable or the like between the control device of the machine tool and the attachment, and conventionally, a flexible cable having a length sufficient to reach within the range of movement of the pallet is used as a input and output cable. For example, a so-called rolling wiring in which the cable is crawled on the floor surface is employed.
In such a prior art as described above, every time the pallet moves, the input and output cable connected to the attachment on the pallet is also moved accordingly, resulting a high possibility of damaging the cable early. Various other problems unavoidably involved in that the range of movement of the pallet is restricted by the length of the cable so that an extra space at a floor is required, that work site becomes disordered, and that star-burst wirings result.